Chem CSET Flashcards
Freon
dichlorodifluoromethane
isolated system
there is no exchange of matter or energy
Closed system
allows for change in energy but not matter
What are the adverse effects of photochemical smog
Human health
damage to materials
toxic to plants
atmosphere
what substance can be found at the highest point of a fractionating column during fractional distillation of crude oil
propane
Which molecules require description with resonance structures
we can write two are more lewis structures that differ only in the position of electrons.
What type of EM spectrum is strong evidence for the big band theory
microwave
isotopes
atoms of the same number of protons but different number of neutrons
Same atomic number
atomc mass number
number or protons and neutrons
Principal quantum number
n
energy level or size of an orbital.
larger moving down a group
Ground state
lowest energy possible
Electron energy level
spdf
s = 1 -2
p =1-6
d = 1-10
f = 1-14
photon
electron transition from high to low energy orbital.
the difference in energy released.
weightless particle of electromagnetic radiation
types electromagnetic radiation
heat light UV light x rays transverse wave
atomic spectrum
each transition H electrons make correspond to a different amount of energy and different color is released
Bohr model
a small positive nucleus surrounded by electrons located in a specific energy level
electron configuration
arrangement of electrons.
1s2
Group 1
alkali metals
soft
silvery
react violently with water
group 17
halogens
extremely reactive and poisonous
metals
shiny
conductive of heat and electricity
malleable
ductile
nonmetals
brittle,
dull
poor conductors
have low melting and boiling points
metalloids
has properties of metals and nonmetals
when determining molecular mass by osmotic measurement the molar mass will
be less
atomic radius
1/2 the distance between the nuclei of two bonded atoms
increase moving down and left
electromagnetic radiation
a form of energy that travels through space
ionization energy
the amount of energy required to remove an electron.
Increases moving up and right.
ionized
losing one or more outer electrons
electronegative
ability to attract other electrons.
increasing moving up and right.
cannot be measured directly.
has no unit of measurement
boiling point
increases then decreases across a period
metallic character along the periodic table
increases moving left and down
chemical reactivity
substances change chemically
photoelectric effect
when electrons are released after light is shone onto a metal
maxwell’s wave theory of light
brighter (high intensity) light would lead to higher energy electrons
quanta
quantities
E = hf
h = 6.63 x 10 ^-34
Quantum theory
F= frequency of radiation
quantum number
describe a specific aspect of an electron
angular/azimuthal momentum quantum number
shape of the orbital l S= o p=8 d=88 f = flower
magnetic quantum number
position of the electron m1 S=0 p= -1 to 1 d = -2 to 2 f = -3 to 3
spin quantum number
s
spin of the electron determines properties of the atom
+/- 1/2
properties of gas
expand to fill container
v of gas = v of container
can be compressed
ideal gas
theoretical that follows a set of principles.
KMT
no volume, attractive or repulsive forces
all collisions are elastic
KE is proportional to temperature
kinetic molecular theory
model used to explain behavior of matter.
particles are constantly in motion.
KE is related to temperature.
space between particles is related to the state of matter.
phase change happens when temperature changes significantly.
intermolecular forces
properties of liquid
fluid and can flow
definite volume but not shape
low compressibility
properties of solids
definite volume and shape
little KE
arranged in a packed crystalline structuer.
amorphous solid
doesnt have crystalline structure
hydrogen bonds
occur between polar molecules that contain an O F N atom covalently bonded to a H atom
dipole induced dipole
occur when a polar molecule induces a temporary dipole moment in a neighboring non polar molecule
dipole
separation of charges between two covalently bonded atoms.
dipole dipole
intermolecular forces between polar molecule.
positive side of a polar molecule attracts negative or another
london dispersion forces
noble gases and non polar molecule
creates temporary dipoles
ion dipole force
force between an ion and dipole molecule
intermolecular forces
positive charged poles attracted to the negative charged poles
phase change
transition from one state of matter to another
sublimination
solid to gas
deposition
gas to solid
phase diagram
graph of the physical state of a substance and the temperature and pressure of the substance
phase equalibium lines
where two phases are in equalibrium
triple point
point where the temperature and pressure conditions are right for all three states to exist together at equilibrium
critical point
gas and liquid states are identical and the substance is in one phase
supercritical fluid
state where the gas and liquid phase of a substance are indistinguishable
dipole moment
overall unequal distribution of electrons across the entire molecule
non polar molecule
even charge distribution and no dipole moment
polar molecule
uneven distribution charge and dipole moment
macromolecule
huge molecules made up of smaller subunits called monomers.
organic macrmolecules
huge molecules that included C and found in living things
inorganic macromolecule
huge molecule not found in living things.
C to F
5/9 (F-32)
Kelvin scale
absolut scale
K
0 is the absolute lowest
K = C + 273
pressure
psi
atm
mmHg
1 atm = 14.7 psi = 760 mmHg
daltons law of partial presures
total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of each individual gas
Pn + Po = Ptotal
diffustion
movement of 1 substance through another
high to low concentration
effustion
gas particles exit through tiny holes in a container
graham’s law
effusion rate of a gas is inversely proportional to the sqr root of its molecular mass.
used to compare the rate of two different gasses at equilibrium.
speed A / speed B = sqr root (mass B/massA)
standard pressure
1 atm = 760 mmHg = 14.7 psi
standard temperature
0 C = 273 K
Avogadro’s number
- 02 x 10 23 amu = 1 mole
1. 2 x 10 ^-7 XRCD
mole
you have 6.02 x 10 ^23 of something
avogadros law
relationship between the number of particles (n) and the volume of a a gas.
V1/ n1 = V2/ne
1 mole of an ideal gas at STP takes up
22.4 L
Boyles law
temperature is held constant the pressure of a gas increases as volume decreases
P1(V1) = P2(V2)
charles law
if pressure is held constant. as the gas is heated its volume will increase
v1/T1 = V2/T2
T must be Kelvin
Gay-lussac’s law
volume of a container is held constant as the temperature increase, the pressure inside the container increases
P1/T1 = P2/T2
T must be kelvin
ideal gas law
relates the temperature, pressure, number of moles and volume of any gas,
PV = nRT
PV = nRT
P = pressure V = volume n = number of moles R = .08216 atm/molK T = Temperature
solvent
dissolves solutes
miscible
liquid dissovles easily in another
immiscible
liquid doesnt dissolve easily in another
ionic compound
compound held together by ionic bonds
formed by transfer of electrons
polar covalent
atoms held together by valence electrons shared between them
nonpolar covalent
valence electrons are shared equally and are no changes in the molecule
Molarity
moles of solute / L of solution
M
molality
mole solute / kg solvent
m
mass percentage
percent by mass of the solute in the solution
{mass solute / mass solution) x 100%
concentration
amount of a substance in a given quantity in a solution
M1V1 = M2V2
Stoichiometry given to unknown
SOLUBILITY
AMOUNT OF SOLUTE NEEDED TO FORM A SATURATED SOLUTION AT A SPECIFIC TEMPERATURE AND SOLVENT AMOUNT.
polarity
unequal sharing of electrons
factors that influence the rate of solution
amount of solute already dissolved.
temperature
pressure and nature
empirical formula
shows the kind and proportions of atoms in substance in simplest form
chemical formula
shorthand of writing a substance by using chemical symbols and number subscripts with the exact numbers of atoms.
Determine percent composition of compounds
write formula.
use formula to determine molar mass.
use molar mass to determine mass percentage of each element.
determine the empirical formula
- find percent composition.
- determine mass composition.
- determine composition in moles.
- find smallest whole number ratio of atoms.
dissolution
dissolving a substance
like dissolves like
calculate frequency
speed of light = frequency x wavelength
pure substance
cannot be separated
homogeneous mixture
unform throughout
solution
alloy
heterogeneous mixture
not uniform throughout
different components can be seen
separating mixtures
manually, dissolving evaporation distillation magnetism filtration crystallization
chromatography
capillary action
retention factor
Rf
distance dye traveled compared to the total distance the solvent traveled
conjugate acid
acid forms when a base gains a proton
conjugate base
formed when an acid loses protons
Acidity Constant
Ka = [H+] [A-] / [HA]
calculating pH of a solution
-log[H3O+]
Must be in molarity
logarithmic
buffer
solution whose pH will not change much when small amounts of acid or base are added to it.
titration
a solution of known properties is used to analyze the properties of an unknown solution
- balanced equation
- V1M1/n1 =V2M2/n2
equivalence point
the amount of H ions and OH ions are equal and pH = 7
where titration stops
indicator solution
chemical that changes color when a specific pH range
Heat transfer
Delta heat = specific heat (m) (delta T)
titration curve
graph of PH vs volume of titration added
determine the unknown substance concentration
[H+][VH+] = [OH-][VOH-]
- gather information
- set up and fill in equation
- calculate
determine pH during titration
- determine mol of each reactant
- determine which reactant is in excess
- calculate pH based on concentration of the excess reactants
titrant
solution of known properties